In November of 2017, a southern California Water Authority retained PICA to inspect 4 miles of 66” C-301, PCCP pipe lined with a 64” steel liner. PICA constructed a special EMIT Tool inside the pipeline, by passing the Tool parts through a manhole and assembling the Tool inside.
Once assembled, the Tool was winched from one manhole to the next one while it collected high resolution thickness data on the liner.
The customer was unsure how sensitive the new Tool was going to be, so, to test its capabilities, they chipped out the cement liner material and installed a pattern of small button magnets. They repaired the cement mortar and waited for PICA to report what they found. The screen capture below shows the signals from the button magnets as the EMIT Tool passed it.
You can see from the pattern, that this customer had a keen sense of humour! The EMIT Tool passed the test with flying colours of course.
Later in the job, PICA detected a local through-hole signal, and the customer decided to check it out. After removing the cement mortar, the customer checked the predicted area using an ultrasonic thickness gauge, and could not find any wall loss; however, on closer examination, it was discovered that the longitudinal weld had a 2” long, through wall crack at exactly the clock position that PICA’s data had predicted! It was the through wall crack that had been detected!
The signal from the crack is shown above and the actual weld at left.
PICA’s EMIT Tool provides extremely high resolution and sensitivity to small local defects, which can grow over time and fail catastrophically when least convenient.
Contact PICA today to discuss how we can help you to inspect your assets to manage them proactively.